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The primary purpose of this study is to analyse the performance of multirotor unmanned aircraft system platforms for passenger transport and compare them with an ordinary helicopter solution. This study aims to define a standard procedure for power budget analysis of unconventional vehicles recently proposed in the aerospace industry, providing guidelines on rotor sizing in terms of required power and the total number of rotors. The ultimate purpose of the proposed work is to describe a methodology for power estimation with regard to emerging electric vertical takeoff and landing (EVTOL) vehicles.

In the context of urban mobility, short-range passenger transport between critical hubs in cities is taken into account and innovative aircraft and traditional helicopters are compared according to a common mission profile. The power budget equations used in the helicopter literature are revisited to consider different multirotor configurations (up to 20 rotors) and evaluate the feasibility of innovative aerospace vehicle design.

The paper includes insights into the maximum number of rotors that ensure a significative, relative power reduction compared to helicopter platforms (the power-to-cruise over power-to-hover ratio appears to be improved). Based on this preliminary analysis, the results suggest the benefit of reducing the installed rotors to avoid excessive power loss in forward flight.

The proposed study provides guidelines for further design considerations and the future development of EVTOL multirotor aircraft.

This paper fulfils the identified need for a systematic approach on performance analysis for innovative vehicles involved in commercial applications.

The results of preliminary tests concerning estimation and widening of helicopter limiting manoeuvre abilities are presented. Research space applies to super‐ and hipermanoeuvrability problems that are especially important for helicopters, because of better manoeuvrability influence on higher safety level and effectiveness in special applications. In airplane engineering, these types of tests are advanced and aerodynamic system improvements are introduced as well as thrust vector control. There are also new manoeuvres recognized for advanced manoevrability airplanes: Cobra, Kulbit, Hook, Bell, Herbst manoeuvre. Although helicopter is “originally” thrust controlled, systematic researches on this field are still not conducted. The paper deals with the problem of helicopter flight mechanics at low flight speeds. The purpose of performed analysis is to achieve possibility of helicopter angular position control within wide range of angular displacements. This is performed by linear and centrifugal acceleration control. Rotor thrust vector control makes those accelerations appear.

For many years prior to the second World War the two volumes of Fuchs and Hopf on Aerodynamics and Flight Mechanics were standard text books in the German language. These books are now out‐of‐date and in consequence some six years ago Professor Schlichting and Dr Truckenbrodt were approached by Dr Springer, the publisher, with a request that they should write a modern successor to the Fuchs‐Hopf volumes. The volume under review is the first of a two‐volume work which they have undertaken. It is not surprising to find that the ground that they plan to cover is somewhat more limited than that of the earlier Fuchs‐Hopf books; the enormous development of the subject in the intervening years has made such a reduction of scope inevitable. In the two volumes it is proposed to cover fluid mechanics (Section A), wing theory (Section B) and the aerodynamics of aircraft including interference effects (Section C), but the mechanics of flight and the aerodynamics of propulsion are topics that are being left to other authors.

The paper aims to detail the educational flight testing activities performed at the Department of Aerospace Science and Technology at the Politecnico di Milano (DSTA-PoliMi), including the development of low-cost, reliable flight testing instrumentation (FTI) and the administration of the graduate course in flight testing.

The flight testing course program closely adheres to the typical content of an introductory course offered in a professional flight testing school. However, within academic courses, it has a unique feature: each student is required to plan, perform and report on a real flight test experience, acting as a flight test engineer. Educational activities in this framework have been successfully matched to applied research and technical support for private companies.

At the educational level, several elements arise that are rarely concentrated within a single course, such as multidisciplinary integration, individual conceive-design-implement-operate (CDIO) project, real-life experimental procedures and techniques, teamwork, communication and reporting, relation with non-academic partners.

Based on the development of a FTI system for light aviation and on the flight testing course, DSTA-PoliMi has built a solid capability in flight testing, introducing graduate students to this specific niche of expertise and empowering co-operation with companies in the light aviation environment, while offering capabilities and tools that are typically regarded as a prerogative of major aerospace companies.

The paper discusses an original approach to flight testing education in an academic setting that avoids the high costs and complexity connected to certified aircraft flight operations and instrumentation, nevertheless allowing the achievement of significant results, also in applied engineering research.

The purpose of this paper is to report the research activity of Politecnico di Torino concerning the MicroHawk platform (micro‐aerial vehicles – MAVs) and to present the design and the development of a basic flight simulator for educational/training purpose.

A simulator is an easy‐to‐use system for the analysis of maneuver response, the dynamic study and the evaluation of the aircraft flying and handling qualities for different aircraft categories. The software implementation, including the definition of mathematical model, the visual scenario and the real‐time data analysis graphic interface, are delineated in this paper. In addition to this experimental phase, an important effort is done to incorporate simulation into the autopilot tuning process.

An intense flight activity is carried out to test the flight control system performances of the MicroHawk platform and to establish general procedures to ensure the correct operation of all subsystems. The automatic flight of MAVs has been studied with success for territorial surveillance and map project.

In order to simplify the use of these platforms by the end‐user, a software interface will be designed to calculate automatically the flight plan, ensuring the desired trajectory design and collision avoidance.

The autopilot simulation integrated with vehicle's dynamics can be used to reduce the platform set‐up time and the risk of losing the prototype. The simulator training permits to study flight complex plane, in order to obtain better platform performances in real conditions. Starting from a simple scenario, it is possible to set up and upgrade the mission at any time during the simulation.

This paper aims to present a new method for identification of some flight modes, including natural and non-standard modes, and extraction of their characteristics, directly from measurements of flight parameters in the time domain.

The Hilbert-Huang transform (HHT), as a novel prevailing tool in the signal analysis field, is used to attain the purpose. The study shows that the HHT has superior potential capabilities to improve the airplane flying quality analysis and to conquer some drawbacks of the classical method in flight dynamics.

The proposed method reveals the existence of some non-standard modes with small damping ratios at non-linear flight regions and obtains their characteristics.

The paper examines only airplane longitudinal dynamics. Further research is needed regarding lateral-directional dynamic modes and coupling effects of the longitudinal and lateral modes.

Application of the proposed method to the flight test data may result in real-time flying quality analysis, especially at the non-linear flight regions.

First, to utilize the empirical mode decomposition (EMD) capabilities in real time, a local-online algorithm is introduced which estimates the signal trend by the Savitzky-Golay sifting process and eliminates it from the signal in the EMD algorithm. Second, based on the local-online EMD algorithm, a systematic method is proposed to identify flight modes from flight parameters in the time domain.

The aim of this article is to determine the simplest and clearest relations existing between the principal characteristics of aeroplanes and their performances.

This paper presents the longitudinal stability analysis of a single tractor propeller airplane LASTA at high engine power settings. This analysis is part of the ongoing process of certifying the airplane for civil use according to the civil regulations CS-23.

The design methodology that is presented in the paper consists of comparing flight test aerodynamic and calculation results. The methods used here are standard and routinely used in flight testing.

Flight testing results indicate that at low airspeeds the cumulative destabilizing effects because of high values of the angle of attack and high power settings are about 6 per cent of MAC. This value is in a very good agreement with published data.

The information presented in this paper are new, and are very specific to this one aircraft configuration. The methods used here are standard and widely used in flight testing.

The information in this paper presents flight test results. There are not many publications in this area.

A standard automatic flight control system – autopilot – will become required equipment of the future aircraft, operating in the common sky. For a specific group of aircraft, they are too expensive and too energy-consuming solutions. This paper aims to present the concept of an automatic flight control system that overcomes those limitations.

The proposed automatic flight control system uses the trim tabs in all prime flight controlling surfaces: elevator, ailerons and rudder, for stabilizing and controlling the steady flights of an aircraft.

The results of an aeroplane flight controlled with the use of trim tabs simulation tests and remarks have been presented and discussed. The simulation was conducted in real-time hardware in the loop environment. The stabilization of the flight was achieved in performed test scenarios.

The possibility to control an aircraft with coordinated deflections of the trimming surfaces is a beneficial alternate to those currently used and can be recommended for use in the next-generation aircraft.

VI.—OUT‐STATIONS IT has already been pointed out that the engineering maintenance department is a minor factor to the major factor of flying operations and, therefore, for maximum overall efficiency it may be necessary to run the engineering side of the work on a basis of over‐suitability. Admitting this state, it becomes expedient to arrange the work so that as little as possible is done by the more inefficient, i.e. the more over‐suitable, sections. Inefficiencies of the kind which will occur in the organization envisaged are caused principally by the necessity for rendering good service under conditions of peak load, and this entails the availability of labour and equipment in excess of normal requirements. This is particularly so at stations on the routes where aircraft stop for traffic and carry on according to a published schedule. The work done at such stations is principally refuelling, re‐oiling and perhaps some attention to cabin conditions. The personnel, however, must be prepared, and able, to attend to any complaint made by the pilot, or to do a daily inspection overnight with whatever preventative maintenance that may entail. In the case of larger aircraft, assistance may be rendered by the flight mechanic, though this assistance should not be counted upon to too great an extent, as the mechanic's flight duties may be heavy on that day or the next, and his alacrity should not be compromised by work which may demand his mental or physical labours during what should be his rest period.